#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<math.h>
int main(void)
{
	float a, b, c;
	double x1, x2,d;
	scanf("Please enter the coefficients a,b,c:\n");
	scanf("%lf,%lf,%lf", &a, &b, &c);
	d = b * b - 4 * a * c;
	if (b * b - 4 * a * c >= 0)
	{
		x1 = (- b / 2 * a + sqrt(d)) / (2 * a);
		x2 = (-b / 2 * a - sqrt(d)) / (2 * a);
		printf("Please enter the coefficients a,b,c:\n");
		printf("x1=%.4f,x2=%.4f", x1, x2);
	}
	else {
		printf("Please enter the coefficients a,b,c:\n");
		printf("error!\n");
	}
	return 0;
}
